Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
  • C08L25/02—Homopolymers or copolymers of hydrocarbons
  • C08L25/04—Homopolymers or copolymers of styrene
  • C08L25/08—Copolymers of styrene
  • C08L25/12—Copolymers of styrene with unsaturated nitriles
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
  • C08L51/04—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to rubbers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
  • C08L51/06—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond

Definitions

• Impact-resistant thermoplastic molding compositions can be prepared by, for example, polymerizing styrene (S) and acrylonitrile (A) in the presence of polybutadiene (B) ("ABS polymers").
• S styrene
• A acrylonitrile
• B polybutadiene
• ABS polymers polymers
• E ethylene
• P propylene
• D nonconjugated diene
• MES polymers ie thermoplastics in which acrylonitrile (A) and styrene (S) are graft-polymerized onto an EPDM rubber (E) are.
• AES and ABS plastics are i.a. from two phases.
• the continuous phase is a copolymer of the grafted monomers, usually a styrene-acrylonitrile copolymer ("SAN-thermoplastic"); the intervening discontinuous phase is the actual graft polymer. Due to its polymerized side chains (“SAN shell”), it is compatible with the copolymer.
• SAN-thermoplastic styrene-acrylonitrile copolymer
• SAN shell polymerized side chains
• German Offenlegungsschrift 1,949,487 describes mixtures of graft polymers of styrene and acrylonitrile with a rubber having a glass transition temperature below -30 ° C. with copolymers of styrene, maleic anhydride and optionally acrylonitrile, which may also contain a copolymer of styrene and acrylonitrile (SAN Resin).
• the graft polymers to be used according to the invention are known. They can be obtained by polymerization of styrene and acrylonitrile in the presence of the rubber. At least a portion of the styrene and acrylonitrile is then graft polymerized onto the rubber. In addition, as a rule, non-grafted styrene-acrylonitrile copolymer is also present.
• the graft copolymers can be obtained in a known manner by radical polymerization of styrene and acrylonitrile in the presence of the rubber in bulk, emulsion, suspension or solution, as well as by combined processes such as bulk / suspension or solution / precipitation polymerization.
• Terpolymers of this construction of acrylonitrile, maleic anhydride and styrene can be obtained by continuous copolymerization under steady state conditions.
• Steady state conditions are used when the concentration of all the reactants and the composition of the polymers formed are constant over the duration of the polymerization.
• Constant conditions occur in a continuously operated and ideally mixed tank reactor after about 0.5 to 24 hours from the beginning of the polymerization. It is necessary to ensure ideal mixing, that is, the Einmisthzeit may only at most 1/10 of the average dwell time in the reactor.
• the continuous polymerization is carried out in a tank reactor with peroxide initiators which at 100 ° C.
• tert-butyl peroctoate has a decomposition rate constant K of .gtoreq.10.times.10.sup.- 3 / sec. -1 own.
• K decomposition rate constant
• tert-butyl peroctoate benzoyl peroxide, lauryl peroxide, tert-butyl perpivalate, isopropyl peroxydicarbonate, 2-ethylhexyl peroxydicarbonate, and acetylcyclohexylsulfonyl peroxide can be used.
• Initiator amounts are preferably 0.01-0.5 wt .-%.
• transfer agents or chain terminators can be used.
• the amount ratio of the monomers fed must be selected so that a polymer of the desired composition is formed.
• the exact monomer composition for a desired polymer must be determined by preliminary experiments. For example, the continuous polymerization of a mixture of 74% by weight of styrene, 22% by weight of acrylonitrile and 4% by weight of maleic anhydride at a steady state conversion of 35% yields a terpolymer which is particularly suitable according to the invention.
• the continuous polymerization under steady state conditions is generally carried out without additional solvents. It is terminated at a conversion of 30-40 wt .-%, the resulting solution of the terpolymer in the monomer mixture is then worked up by evaporation and recycling of the recovered monomers in the process. To evaporate the solution, the usual methods are used, for example flash evaporation, screw evaporation, thin film evaporation or falling film evaporation and spray drying.
• Terpolymers whose acrylonitrile content is in the range of the acrylonitrile content of the graft polymers are particularly suitable for the molding compositions according to the invention.
• the molding compositions according to the invention show, in comparison to molding compositions of the same graft polymers and SAN copolymers good flowability and unabated good toughness level at at least 12 ° C increased heat resistance.
• the molding compositions of the invention are particularly advantageous where it depends on good weather resistance, high heat resistance, high toughness and ease of processing.
• they may advantageously be used chemically to produce pipelines, high quality gaskets, utensils, steam sterilizable appliances, washing machine parts, battery boxes, dry battery housings, housings and other insulating parts in electrically powered machines, electrical insulating films, saponification resistant container liners and thermally resistant filter cloths and many other things.
• EPDM rubber based on dicyclopentadiene (iodine number 11, Mooney 70) are dissolved in 300 parts of benzene. 37.5 parts of styrene and 14.5 parts of acrylonitrile are added and the solution is heated to 120.degree. After addition of 0.9 part of di-tert-butyl peroxide is polymerized for 12 hours. 0.5 part of 2,6-di-tert.-butyl-p-cresol is then added to the polymer solution and the polymer is isolated by stripping. The polymer product is dried at 70 ° C in a vacuum oven.
• the initiator also becomes continuous added to the reactor: 0.6 parts tert-butyl perpivalate (75% in dibutyl phthalate) per hour, so that after about 2 hours, a polymer solution with about 30% solid is formed.
• the solution of the polymer in the monomers removed is admixed with 0.1% by weight of 2,6-di-tert-butyl-p-cresol and then freed from the monomers and the volatile constituents on a steam extruder.
• the SAMA copolymer contains 17% by weight of acrylonitrile, 12% by weight of maleic anhydride and 71% by weight of styrene.
• the fractionation was carried out from dimethylformamide with cyclohexane at 78 ° C.
• Table 1 shows the mixtures of the graft polymer (A) with copolymers of different compositions. which were prepared analogously (B) listed.
• B a commercially available SAN copolymer of 75% by weight of styrene and 25% of acrylonitrile having an intrinsic viscosity of 0.70 dl / g is used.

Landscapes

• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Graft Or Block Polymers (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=6022199

Family Applications (1)

Country Status (7)

Families Citing this family (7)

Family Cites Families (9)

• 1977
  • 1977-10-26 DE DE2747823A patent/DE2747823C2/de not_active Expired
• 1978
  • 1978-10-14 EP EP78101145A patent/EP0001624B1/fr not_active Expired
  • 1978-10-14 DE DE7878101145T patent/DE2860848D1/de not_active Expired
  • 1978-10-20 US US05/953,000 patent/US4163032A/en not_active Expired - Lifetime
  • 1978-10-24 IT IT51613/78A patent/IT1106224B/it active
  • 1978-10-24 CA CA314,139A patent/CA1109582A/fr not_active Expired
  • 1978-10-24 JP JP13011778A patent/JPS5473844A/ja active Granted
  • 1978-10-25 ES ES474500A patent/ES474500A1/es not_active Expired

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events